1. Field of the Invention
The present invention relates to a wireless communication system. More particularly, the present invention relates to a method and an apparatus for tracking a beam in a wireless communication system.
2. Description of the Related Art
Wireless communication systems have developed in a direction for supporting a higher data transmission rate in order to meet continuously increasing wireless data traffic demand. Recently, 4-Generation (4G) wireless systems have been pursued as a technology for improving a spectral efficiency generally in order to increase a data transmission rate. However, it is difficult to meet an explosively increasing wireless data traffic demand using only such a spectral efficiency improvement technology.
In order to address the increasing demand, a very wide frequency band may be used. Yet, since it is very difficult to secure a wide frequency band in a frequency band that is less than 10 GHz and is currently in use, a higher frequency band needs to be secured. However, as a transmission frequency for wireless communication is increased, the distance of reach, i.e., the range, of a radio wave gets relatively short, and there is a reduction of coverage area. In order to increase the distance of reach of the radio wave, a beam-forming technology may be used.
Generally, transmission beam-forming is a method for concentrating a region of propagation or transmission of a radio wave in a specific direction using a plurality of antennas. A plurality of antennas which are arranged together is referred to as an antenna array, and an antenna included in the antenna array is referred to as an array element. When transmission beam-forming is used, a transmission distance of a signal may be increased, and since the signal is generally not transmitted in other directions except for a relevant direction, interference from other user signals may be reduced significantly.
Meanwhile, a reception side, or a receiver, may perform reception beam-forming using a reception antenna array. Reception beam-forming also concentrates reception of a radio wave in a specific direction to increase a gain of a signal entering the receiver from a relevant direction and may exclude a signal entering from other directions except for the relevant direction, thereby excluding interfering signals. To perform basic beam-forming, a technology for allowing a base station and a terminal to efficiently select a transmission and/or reception beam is required. In addition, if a beam is not correctly set due to a specific error during a transmission and/or reception beam setting process, then spectral efficiency deterioration may occur. Accordingly, a base station should be allowed to control an error state and a stable beam tracking method should be provided.
Therefore, a beam tracking method and an apparatus thereof, for efficiently selecting a transmission and/or reception beam-forming in a wireless communication system are required.
The above information is presented as background information only to assist with an understanding of the present disclosure. No determination has been made, and no assertion is made, as to whether any of the above might be applicable as prior art with regard to the present invention.